Engaging in leisure activities such as reading a book, visiting friends, or walking may help reduce your risk of developing Alzheimer’s disease, according to researchers at Columbia University. These activities may decrease the risk of incident dementia, possibly by providing a cognitive reserve that delays the onset of clinical manifestations of the disease, the investigators reported in the December 26 Neurology. “Maintaining intellectual and social engagement through participation in everyday activities seems to buffer healthy individuals against cognitive decline in later life,” said Yaakov Stern, PhD. A total of 1,772 non-demented individuals ages 65 and older participated in the study. Subjects’ leisure activities at baseline were assessed, and annual examinations were performed for up to seven years. The risk of dementia was decreased in subjects who participated in leisure activities.

The U.S. Food and Drug Administration has approved Activa Parkinson’s Control Therapy to help relieve the debilitating slowness, stiffness, and shaking of Parkinson’s disease. Activa therapy can also reduce the duration of the dyskinesias that are a common side effect of medications for the disease. The therapy delivers controlled pulses of electrical stimulation to targeted areas of the brain using an implanted medical device. It is intended as an adjunctive treatment for patients in advanced stages of Parkinson’s disease who still respond to levodopa but whose symptoms are not adequately controlled by medications. The Activa system is marketed by Medtronic.

Researchers at the University of California, Los Angeles, have observed altered brain function in people who respond favorably to placebo treatment for major depression. These changes are different from those found in people who respond to antidepressant medication, said the investigators in the January American Journal of Psychiatry. The study involved quantitative EEG imaging to examine brain activity in patients treated for depression. Patients who responded to placebo showed increased activity in the brain’s prefrontal cortex, and those who responded to medication showed suppressed activity in that area. Overall, 52% of the subjects receiving antidepressant medication responded to treatment, and 38% of those receiving placebo responded.

Folic acid deficiency could increase the brain’s susceptibility to Parkinson’s disease, according to a report in the January Journal of Neurochemistry. Researchers at the National Institute on Aging fed one group of mice a diet that included folate, while a second group was fed a diet lacking this vitamin. The investigators then gave the mice moderate amounts of a neurotoxic chemical that causes Parkinson’s-like symptoms. In the mice that received dietary folate, the neurotoxin caused only mild symptoms of the disease. The mice fed the folate-deficient diet, however, developed severe Parkinson’s-like symptoms. “This is the first evidence that folic acid may have a key role in protecting adult nerve cells against age-related disease,” said Mark Mattson, PhD. “It is clear from this study that a deficiency of this vitamin is associated with increased toxin-induced damage to the dopamine-producing neurons in the mouse brain.”

Lifetime exposure to hormone replacement therapy (HRT) may be associated with better maintenance of cognitive function in older women free of dementia. As detailed in the December 26 Neurology, more than 2,000 women ages 65 and older were assessed using the Modified Mini-Mental State Exam and a simplified version of the depression section of the Diagnostic Interview Schedule. The participants were followed for three years to assess changes in cognition and depression status and additionally provided detailed information regarding use of HRT. “This study shows an apparent benefit of lifetime HRT use on cognitive function in non-demented older women,” said Michelle C. Carlson, PhD, of Johns Hopkins University. “And those who stand to lose the most cognitively—women over age 85—appear to gain the most from HRT exposure.”

Researchers believe that both HIV and Alzheimer’s disease cause brain damage involving inflammation, suggesting that anti-inflammatory drugs could help in treatment. Findings from a study in the January 4 AIDS show that AIDS dementia, like Alzheimer’s disease, may be a chronic condition and that immune cell markers of AIDS dementia remain even after a patient is treated with antiretroviral drugs. These same markers are elevated in patients with Alzheimer’s disease. “The brain wages an immune response against HIV infection,” said Lynn Pulliam, PhD, of the San Francisco Veterans Affairs Medical Center. “We believe that the brain is damaged by inflammatory toxins that are released as part of the brain’s immune response. The amyloid plaques of Alzheimer’s are also believed to cause a toxic inflammatory response.”

Major differences in the procedures used to diagnose brain death in adults exist throughout the world, according to a study in the January 8 Neurology. Although there is agreement on the neurologic examination used to determine brain death, researchers found considerable differences in the number of required physicians, in mandated level of experience and academic rank of physicians, in specialty preferences, and in recommendations of confirmatory tests. Other variations in procedures included observation time from first diagnosis and methods of apnea testing. Brain death guidelines or code of practice were present in 70 of the 80 countries that responded to a survey, and official legal standards on organ donation were present in 55 countries.

Israeli researchers have shown that high triglycerides are a strong independent predictor of stroke risk. Thus, they emphasize that health care providers should include triglycerides as part of their global risk assessment for stroke in all individuals and know that people can have elevated triglycerides even if their cholesterol is normal. “More effective screening and detection of high blood triglycerides and treatments to modify this stroke risk factor could further reduce the health burdens of stroke,” said lead author David Tanne, MD. Individuals who had a stroke or transient ischemic attack had higher than average levels of triglycerides and lower levels of high-density lipoprotein cholesterol. The study appears in the December 11 Circulation.

Children who are hospitalized for bacterial meningitis do not always sustain long-term neurologic damage, according to a study in the November Journal of Child Neurology. Researchers from Washington University found that 185 patients who had been hospitalized for severe bacterial meningitis between 1973 and 1977 showed no signs of lower intelligence over the years, as measured by several standardized tests. The study’s results “support the conclusion that lacking evidence of gross neurologic complications, the cognitive functioning of children who have recovered will fall within the normal range and be comparable with that of full or half siblings,” said lead author Philip R. Dodge, MD. Overall, the test scores improved slightly, and there were no significant changes between patients and their siblings on any test.

Minocycline may be a potential treatment for multiple sclerosis, according to a study in the December Annals of Neurology. The antibiotic was tested in rats with autoimmune encephalomyelitis, a condition that mimics multiple sclerosis. Results demonstrated that treatment could significantly decrease the severity of disease attacks or even block the onset of relapses. “Animals treated with minocycline did not develop neurologic dysfunction or had a less severe course than untreated rats,” said Ian D. Duncan, PhD, of the University of Wisconsin–Madison. “This clinical difference was confirmed by the relative lack of pathologic change in the nervous system of treated animals,” he added. The investigators believe that minocycline may target microglial cells, which raises the possibility that the drug also could be used in other neurologic diseases.

Researchers have found that two enzymes involved in the production of amyloid-ß protein are increased inside the muscle cells of patients with inclusion-body myositis, in which amyloid-b is also increased. BACE1 and BACE2 are enzymes that selectively snip the amyloid precursor protein to create the presumably toxic amyloid-ß and are found in normal tissues at very low levels. “We have found an increase at the protein level of these two enzymes for the first time ever in a human disease,” said Valerie Askanas, MD, PhD, of the Keck School of Medicine of the University of Southern California. The finding has implications for developing treatments for inclusion-body myositis and possibly Alzheimer’s disease. The study appeared in the December 8 Lancet.

Women with epilepsy have an increased risk for developing premature ovarian failure, a finding that should be considered in counseling women with epilepsy on family planning, said researchers at Georgetown University. As reported in the December Epilepsia, the investigators interviewed 50 cognitively normal women with epilepsy, ages 38 to 64, whose seizures began before age 41. Seven of the 50 women (14%) with epilepsy had nonsurgical premature perimenopause or menopause, compared with three of 82 (3.65%) in the control group. No statistically significant association was found between premature ovarian failure and antiepileptic drugs. In addition, women with premature ovarian failure were more likely to have had catamenial exacerbation of their seizures than were women without premature ovarian failure.

NR